Control/Dimming L21-30 for portable dimmer power

i am trying t add a small number of portable dimmers to a semi-permeate truss rig that will have primarily LED's.
the leds will be powered with a 6 circuit lex bento box with L21-30 pass thru, fed from a cam-> 5- L21-30 pagoda.
since there will be a lot of motors wanted to keep the cable the same.
i am leaning towards ETC merely because everytime i have walked away fro them i've regretted it. cost is somewhat of an issue. ive looked at the smart modules but they are a little short oc dimmers and im over powered. my preference is the smartPack probably 12x10 (i'm going back and forth.) i assume that i can set the head on the dimers so i don't exceed my 30A 3P feed, (less the LEDs). the conventionals would be ellipsoidals. with FOH being mainly branding gobos and the stage pack being highsides for dance, etc.
any advice on either another pack to look at or that this is a terrible idea would be appreciated.
thanks curtis
 
My go to shoe box dimmer pack has always been Leprecon. About as reliable and bulletproof as I’ve ever seen.

I like and use ETC almost exclusively for all else, but always thought they should have just bought out CAE way back before they started the Smart line of products.
 
... i assume that i can set the head on the dimers so i don't exceed my 30A 3P feed ...
any advice on either another pack to look at or that this is a terrible idea would be appreciated.
Not a terrible idea, just a few caveats.
(In no particular order.)
1. You actually have less than 30A per leg available, for two reasons.
a. You have four current carrying conductors in your 10/5 cable. See NEC table 400.5(A)(1) for rating.
b. Because of dimmers' triplen harmonics, the neutral may be carrying up to 130% current.
2. OTOH, you're probably not loading every 10A dimmer with 1200W, right? Twelve 750W SourceFour s, one per dimmer = 25A per leg. BUT, 24x575= 38A/leg. So don't do that.
3. Assuming "set the head on the dimers" means set a max voltage either at the dimmer pack or on the console, is a bad idea for a number of reasons.
a. What level do you set? 90%, 75%. Incandescent lamps draw current exponentially with respect to voltage, not linearly.
b. Your color temperature will be lower than expected at "full". Likewise intensity.
4. Not sure what the strain-relief situation is with the SmartPack, as I think it's supposed to be installed in a rack. Sounds like you want to have them loose. https://www.controlbooth.com/threads/diy-mounting-etc-smartpack.20604/#post-185959 discusses install, SL620 & SL1210 are suitable loose, provided they have output connectors and not terminals.
5.An old relevant thread https://www.controlbooth.com/threads/proper-plug.26170/ .
I'm sure I'll think of more later.

@SteveB, I agree Leprecon is great, but last I looked, they didn't have comparable items to SmartBar and SmartModule.
 
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Voltage drop and loading. Company standard existing long before me starting 19 years ago in me following set safe policy. A few years ago, me allowing 10/5 to exist in 25' lengths or shorter but in no other cases.

A note by one of my guys last week while working on a AC-Distro broken circuit breaker repair... the L21-30 receptacle (Forget which brand Lex or Motion! Labs), it's only fed by #12 MTW wire! These are UL listed AC Distro racks! Yea, per my permission re-wire to #10 MTW and to keep an eye on future racks for re-wiring to our standards..
 
My go to shoe box dimmer pack has always been Leprecon. About as reliable and bulletproof as I’ve ever seen.

I like and use ETC almost exclusively for all else, but always thought they should have just bought out CAE way back before they started the Smart line of products.
Those are nice dimmers and are actually what I use, however they won't help the OP since they can't be directly powered by a L21-30 without downstream breakout distribution.
 
Not a terrible idea, just a few caveats.
(In no particular order.)
1. You actually have less than 30A per leg available, for two reasons.
a. You have four current carrying conductors in your 10/5 cable. See NEC table 400.5(A)(1) for rating.
b. Because of dimmers' triplen harmonics, the neutral may be carrying up to 130% current.
2. OTOH, you're probably not loading every 10A dimmer with 1200W, right? Twelve 750W SourceFour s, one per dimmer = 25A per leg. BUT, 24x575= 38A/leg. So don't do that.
3. Assuming "set the head on the dimers" means set a max voltage either at the dimmer pack or on the console, is a bad idea for a number of reasons.
a. What level do you set? 90%, 75%. Incandescent lamps draw current exponentially with respect to voltage, not linearly.
b. Your color temperature will be lower than expected at "full". Likewise intensity.
4. Not sure what the strain-relief situation is with the SmartPack, as I think it's supposed to be installed in a rack. Sounds like you want to have them loose. https://www.controlbooth.com/threads/diy-mounting-etc-smartpack.20604/#post-185959 discusses install, SL620 & SL1210 are suitable loose, provided they have output connectors and not terminals.
5.An old relevant thread https://www.controlbooth.com/threads/proper-plug.26170/ .
I'm sure I'll think of more later.

@SteveB, I agree Leprecon is great, but last I looked, they didn't have comparable items to SmartBar and SmartModule.
I agree with the above. There's no practical way to limit the input current for the Smartpack (or any other dimmer) other than to use care when loading fixtures. Some power amplifiers can do what the OP is thinking which is automatically reducing the output of the amp to keep it under a particular input current, however I'm unaware of any dimmer that has active load monitoring - normally they rely on the channel circuit breaker for over-current protection.

FWIW, I owned a Smartpack eons ago and while it was a nice dimmer, it was a pain to power it short of having a full distro like the OP is describing. I moved to the Leprecon ULD-HP packs that SteveB mentioned and though they can't be directly powered by a L21-30, they are a lot more flexible since they can be powered by regular Edison circuits.
 
I agree with the above. There's no practical way to limit the input current for the Smartpack (or any other dimmer) other than to use care when loading fixtures. Some power amplifiers can do what the OP is thinking which is automatically reducing the output of the amp to keep it under a particular input current, however I'm unaware of any dimmer that has active load monitoring - normally they rely on the channel circuit breaker for over-current protection.

FWIW, I owned a Smartpack eons ago and while it was a nice dimmer, it was a pain to power it short of having a full distro like the OP is describing. I moved to the Leprecon ULD-HP packs that SteveB mentioned and though they can't be directly powered by a L21-30, they are a lot more flexible since they can be powered by regular Edison circuits.

Which begs the question as to why pass thru on a L21-30 in the first place. I would not be putting a Bento box out on an electric in the first place as there's no hanging mechanism.

I'd use existing dimmed circuits converted to relays, with Lex E-Strings for distribution for the LED's that are not using pass thru's (or even that are). Then 4 dimmer packs off add'l relay outlets.
 
Which begs the question as to why pass thru on a L21-30 in the first place. I would not be putting a Bento box out on an electric in the first place as there's no hanging mechanism.

I'd use existing dimmed circuits converted to relays, with Lex E-Strings for distribution for the LED's that are not using pass thru's (or even that are). Then 4 dimmer packs off add'l relay outlets.
The OP hasn't indicated that he has any fixed dimming infrastructure. I took this to be more of a portable setup rather than a fixed theater, but could be wrong.
 
The OP hasn't indicated that he has any fixed dimming infrastructure. I took this to be more of a portable setup rather than a fixed theater, but could be wrong.

Yup, "since there will be a lot of motors wanted to keep the cable the same.".

OK, see that, makes sense.

The Leprecon's I like are normally 2 - 120v/1 pole inputs per pack, your choice of connector. I know I've seen the Leprecon 4x packs setup as a single 30a, 2 pole feed with a twist, likely the same L21-30. The Chamber Theater touring group out of Bposton I work with all the time, uses these and uses twist feed cables back to a Lex distro. So I think Leprecon can make them, but the ETC SmartModule 4 pack comes this way anyway, and takes a clamp.
 
If you are powering LED’s - try an ETC Colorsource relay - wired or wireless. Nice clean way to manage the data and power.
Don’t use dimmers to power LED’s. Good rule of thumb.

Yeah, maybe somewhat unclear as to intended use for the dimmers,. The OP made this comment;

"the leds will be powered with a 6 circuit lex bento box with L21-30 pass thru, fed from a cam-> 5- L21-30 pagoda."

Thus I think we assume the Bento feeds direct to the LED's, while the dimmer packs will get pass-thru from the Bento's for conventionals on dimmers.

We think.
 
I've been having a lot of trouble with my ULD-360s for the last couple years. Unfortunately the best answers I'm getting is to replace all the guts.

For portable 3-phase systems like this, I've had a lot of luck with the ETC Smartbars. They have a direct 3-phase input version, and have through hole bolts for mounting. They are used more often for permanent or semi-permanent installations, but it seems like the right fit here.
 

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